This invention refers to a lock-up clutch for a hydrodynamic flow converter with a pump-wheel, a turbine-wheel and guide-wheel. The pump-wheel and the turbine-wheel are centrally located within a fixedly mounted cover of the converter. Between the converter cover and turbine blades there is a ring piston having a conical clutch surface at its outer periphery for coacting with an inner surface of the cover. The turbine wheel has a sealing hub and a counter seal-hub which is used as the driving element for the ring piston. A damper unit having annular damper elements is mounted on the ring piston.
Lock-up clutches of this general type are already known. German Patent DE-05 32 36 621 describes a lock-up clutch with a pre-installed piston damper device for a hydrodynamic flow-unit. In this lock-up clutch there is a ring piston designed with a conical friction surface between the turbine blades and an enclosing converter cover. There is also a damper unit arranged between the traction surface and the converter pump-wheel, which pump wheel is fixedly mounted to the converter cover.
The damper unit of the aforementioned lock-up clutches comprises a damper with torsion spring means, which are constructed in annular fashion and disposed on the side of the ring piston that is directed toward the converter cover. The spring is located between the damper seal-hub and a corresponding conically shaped counter-friction surface co-acting with the converter cover traction surface.
The basic function of the lock-up clutch of the aforementioned kind and its aim is to provide an axially compact construction. It also provides the possibility of a resilient damper construction with large angular torsion possibilities.